Concrete-mixer.



T. AHLBORN.

CONCRETE MIXER.

APPLICATION FILED MAY 14, 1912.

1,075,000. Patented Oct. 7, 1913.

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COLUMBIA ELANOGRAPH 60., WAsmNp'rON. D. c.

T. AHLBORN.

CONCRETE MIXER.

APPLICATION FILED MAY 14,-1912.

Patented 0015.7, 1913.

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FEET STATES ATNT FFTQE.

THEODORE AHLBORN, OF WATERLOO, IOWA, ASSIGNOR TO THE WATERLOO CEMENT MACHINERY CORPORATION, OF WATERLOO, IOW'A.

CONCRETE-MIXER.

Specification of Letters Patent.

Patented @ct. '7, 1913.

Application filed May 14, 1912. Serial No. 697,289.

To all whom it may concern:

Be it known that I, THEODORE AI-ILBORN, a citizen of the United States of America, and a resident of Waterloo, Blackhawk county, Iowa, have invented certain new and useful Improvements in Concrete-Mixers, of which the following is a specification.

My invention relates to improvements in concrete mixers, and the objects of my im provements are, first, to provide a stationary rotatable mixing drum with suitable means for delivering its contents when de sired, coupled with means for preventing a delivery; second, an improved system and arrangement of mixing-blades provided on the inner wall of the mixing-drum, to more perfectly and more expeditiously mix the contents of the drum; third, the addition to said mixing-drum of a concentric deliverydrum, having means for delivering its contents into the mixing-drum, and finally, an improved method of construction of the mixing-drum body, whereby it may be framed from zonal sections having connecting-means and arranged for the insertion therebetween of a sprocketor gearrim, with means for sealing the edges of said sections to each other and to said rim so as to prevent exudation of liquids contained in the drum.

These objects I have accomplished by the mechanism which is hereinafter described and claimed, and which is illustrated in the accompanying drawings, in which:

Figure 1 is a front elevation of my improved concrete mixer, parts being broken away. Fig. 2 is a longitudinal central vertical section of the mixingand deliverydrums of said mixer. Fig. 3 is a rear elevation of the delivery-drum, with the rear annular plate of same sectioned vertically away to disclose the interior construction. Fig. 4 is a rear elevation of the deliveryconduit for the mixing-drum. Fig. 5 is a transverse section of the troughed cover of the said conduit, taken across the higher portions of the side-walls thereof. Fig. 6 is an enlarged transverse section of the joint in the mixing-drum,which shows the gearrim seated between." the edges of the zonal sections of said drum, with the means for sealing said parts together, and parts being broken away. Fig. 7 is a similar section taken through two of the sealed edges of the zontal sections or plates of said mixing-drum. Fig. 8 is a view of that part of the inner cylindrical wall of the mixing-drum which contains the projecting mixing-blades, developed as a plane surface. Fig. 9 is a plan view of a mixing-blade, in which the form is varied to widen it at its angle of bending. Fig. 10 is a similar view of a mixing-blade whose form is varied by narrowing it at its angle of bending.

Similar numerals of reference denote similar parts throughout the several views.

My improved mixing-drum is of cylindrical form, and is composed of a plurality of sections of ring-shape, which form the concentric zones 1, 2 and 3, which are united at their edges by means to be hereinafter described. The front and rear plates 1 and 3 have front and rear Walls respectively, which are centrally o-rificed to provide delivery and reception ports. The drum is rotatably mounted on traveleror antifriction Wheels 30, 31 at the front and rear, the said wheels being secured on opposite ends of axles 32 which rotate in bearings 33 and 34 on supporting beams 35 and 36 respectively. The sections 1 and 3 of said drum have thickened and projecting annular runways t and 5 respectively, which seat themselves movaloly on said traveler wheel rims.

In order to economize by saving the machining of the connected edges of the drum segments 1, 2 and 3, I have adopted novel means for securing said segments or plates together, and sealing them to prevent exudation of liquid through the joints. The sections 1, 2 and 3 are preferably made of iron castings, formed with outstanding rims about their contacting or adjacent edges, as shown at 7 8, and 11, 12. In the simple joint between the edges of the plates 2 and 3, the adjacent faces of said edges and rims are brought together, and the rims 11 and 12 are connected as tightly as possible by means of the bolts 13 and nuts 1%. In the compound joint between the sections or plates 1 and 2, similar bolts 9 and nuts 10 are employed to secure the rims 7 and 8 together, but in this joint 1 have included or seated'the sprocketor gearrim 6 between the edges and rims of said plates. The inclusion of this gear-rim effects a double purpose, that of bringing the gear-teeth nearer to the outer periphery of the drum, but also in the saving of material in'including the body of the gear-rim as part of the wall of the drum. The edges of the sections not having been machined, are not perfectly smooth, as when planed, but a tight joint in each case is secured by the following means.

Referring to the simple joint shown in Fig. 7, it will be seen that the contacting edges of the plates 2 and 3 have opposite grooves of such a like contour as will, when the edges are associated together, produce an annular cavity about the drum at 69 of an elliptical cross-section with the longer diameter of the ellipse radial. I seatin this elliptical cavity, as a sealing-means, a ring of lead or other suitable material, which is sufficiently soft and compressible yet capable of retaining its shape when com} pressed, and which is preferably circular in .crosssection, with the circular diameterwider than the width of the less diameter of said elliptical cavity, and whereby when the walls of said cavity are forced together, the

compression exercises upon the lead ring some distortion of figure, causing it to tightly seal the cavity, and prevent exudation of liquid from the drum. The shape of said cavity 69 may be varied as well as the form and materials of said sealing-ring, without departing from the scope and principle of my invention. I have also adopted additional connecting and securing means for the joint, which consist of an annular ridge Y2 on the edge of the plate 3 adapted to enter and lit a counterpart hollow on the abutting edge of the plate 2. This connection of the tongue and groove variety, serves to lock the parts of the drum more securely against the effects of transverse stresses.

The compound joint shown in Fig. 6, where the gear-rim 6 is included between the edges and rims of the plates 1 and 2, displays the same kind of sealing and securing means as already described, but. the elliptical cavities are found on each side of the gear-rim at 64 and 67, and the sealing-rings at 65 and 66 respectively. Said gear-rim is also locked by similar tongue and groove joints 62 and 63 respectively. Said mixingdrum is supported on a truck-frame 51, the latter mounted on the carrying-wheels 52 and 53, and said frame 51 supports a superstructure of uprights 49 and 50, and 19, with longitudinal beams 48, 39 and 42, which have each functions to be described. An ranged at equal distances apart transversely of the inner wall of the cylindrical part of said mixing-drum are the several mixingblades 16, 17, etc., projected into the interior of the drum. I have preferably formed. these mixing-blades with a bent contour, the angle of bending occurring nearer one end than the other, and said blades being ar ranged in the drum as to alternate with each other, so that the short bent end of each lies between the long bent ends of the blades on either side, and vice versa. The result of this form and arrangement of the blades, is

the drum.

blade when received thereon to the trough of its angle, and then is discharged in the same manner, which causes the materials to be moved reversely through the drum longi.- tudinally as well as across its interior, which quickly mines it together,

The thoroughly mixed materials are discharged from the miXing-drumin the fol lowing manner. A cylindrical chute or conduit 18 is fixedly connected to and'supported by the frame uprights 19, and lies in an inclined position, with its uppermost and rear end projected into the delivery opening of the drum. 7 The receiving inner end of said chute, as shown in Figs. 2 and 4, is widened and made rectangular at the top and pro-' vided with an obliquely inclined hood 29 with curved lower edge, and whose ends are spaced away to form grooves 44 at each end. The lower part of the upper end of said chute has a forwardly-directed relatively large hollow or socket 24, and on either side of said socket are bearings 45 integral with the chute in whose hollow 24 is inserted the alined bearing 28 on the under side of an upwardly-tronghed pivoted cover 21 said bearings 45 and the bearing 28 having a pintle 22 seated in alined orifices therein, and on which the part 28 is pivotet. The raised sides of said cover 21 which form a rectangular trough project upwardly in an angular form from front to rear and are seated to move in the grooves 44 of the upper partof the chute l8.

28 is a longitudinal rib on the bottom of the cover 21. The forward part of the bot,- tom wall of said cover 21 projects forwardly beyond said side walls enough to engage and close the opening under the depending part 29 of the chute when said cover 21 is tilted rearwardly, as shown in full lines in Fig. 2. In the latter position, material in said mix: ing-drum which is projected toward the chute opening is arrested by the raised bottom wall of said cover and runs down into the drumagain over the trough of the cover formed by its side walls. A. deflecting-plate 20 on either side of said cover, set a little above its side walls and somewhat obliquely inclined toward the cover, aids in carrying the materials into the trough of the cover. This plate 20 is secured across the upper part of the fixed chute 18, and inclined in: wardly, so as to close the opening between the fixed chute and the adjacent end of the tiltable chute 21 when the latter is tilted to return materials deposited thereon back into The said plate 20 has integral wings extending back over and along the upper edges of the flanges of said tiltable chute, and inclined toward suchedges, so that when material falls from the drum mixing-blades upon them, such materials are deflected thereover into the tiltable chute. The delivery edge of the tiltable chute may be convex to fit the concave abutting edge of the plate 20 if desired, and notched at 44 to receive the flanges of the chute 21 to hold the parts in position.

The following means are employed in order to tilt the cover 21 to and fro. On the bottom of said cover is a bearing lug 27, and has a pintle which pivotally connects said lug to the rear end of a link 26. The for ward end of the link is pivoted to the lower member of a bellcrank lever formed of the handle 47 and the member 25. When the handle is shifted in one direction, the cover 21 is tilted forward as shown in the full lines in Fig. 2, and is then in a position to close the chute 18, but when the handle is shifted oppositely, the cover is tilted back to the position indicated by the dotted lines in said figure, opening the chute, and permitting materials which are projected on the cover to slide thereo-ver into the chute for delivery to some receptacle outside.

I have adopted an improved means for delivering materials into the said mixingdrum, which consists of a delivery drum 15 of hollow cylindrical form, having a delivery opening registering with the receiving opening of the mixing-drum, also having a larger concentric receiving opening at the rear. The two drums are secured together to rotate as one, and the drum 15 has inte rior blades or integral buckets 38 arranged transversely at equal intervals about its inner cylindrical periphery, as shown in Fig. 8. These buckets 38 are preferably made with a parabolic curvature so as to hold a considerable amount of material, while quickly delivering it across the drum and into the inclined hopper or chute 37, the lat ter delivering into the receiving opening 68 of the mixing-drum, and being supported by the cross-beam 39. The unmixed materials may be placed in the drum 15, by dumping the same from a wheelbarrow 43, whose delivery-lip may be fulcrumed on the horizontal angle-bar 1-2, the latter being located at the lower part of the receiving-opening of the drum 15. The lower end of the chute 37 may be further supported by means of a bracket 1O projected forwardly from a cross beam 41. The drum is rotated by means of a pinion 56 meshed in the gear-rim 6, and said pinion is on the same shaft 55 as a larger gear-wheel 54, the latter being driven by a pinion 57 on the crank-shaft 58 of an engine (not shown), which carries the flywheel 59. Other means of driving the machine or rotating the drum may be employed without deviating from my principle of invention.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is:

1. In combination, a rotatable drum having reception and delivery ports, and mixing-blades secured to the inner wall of said drum, spaced apart, and said blades being bent near one end to form a short trough near that end, the blades being arranged to alternate the long ends with the short ends of the troughs about the drum.

2. In combination, a rotatable drum having reception and delivery ports, and mixing-blades projecting inwardly on its inner cylindrical wall, spaced apart, said blades being bent near one end to form a short trough near that end, the blades being arranged to alternate the long ends with the short ends of the troughs about the drum, the part of each blade at its angle being of a different width from the other parts of the blade to deliver successively therefrom into oppositely located zones of the drum.

8. In combination, a rotatable drum having a delivery orifice, a tiltable chute mounted within said drum, a fixed chute mounted without said drum and having one end extended through the delivery-orifice of the drum and adapted to receive materials from the adjacent end of the tiltable chute when the latter is tilted toward it, and a deflecting body fixed across the upper inner end of the fixed chute and adapted to close the gap between itself and the adjacent end of the tiltable chute when the latter is tilted back to deliver materials into the drum, said deflecting-body having rearwardly directed projecting blades located over the lateral edges of the tiltable chute and inclined toward the chute, and adapted to cooperate with the said deflecting-body in conveying materials into said chute which are deposited thereon by the drum while in rotation.

Signed at Waterloo, Iowa, this 26th day of April, 1912.

THEODORE AHLBORN.

Witnesses W. H. BRUNN, WV. P. HoxIE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Yatents. Washington, D. 0." 

